be interesting to see what the reaction of the japanese people is when they hear this news because america is the strongest ally. and i think for them to say that their people need to leave the dependence of their embassy personnel said that there's a recognition that there is some danger here. >> nbc's lester holt now with the latest on the frantic effort to stop that nuclear crisis. >> reporter: there are concerns tonight about a possible breach in the containment vessel at reactor 3. a confirmed breach in reactor 2 is already leaking radiation. and there are new fears at the all-important water cooling the still highly radioactive spent fuel rods at reactor 4 is dangerously low. workers were temporarily evacuated during the night. and a water drop by helicopter was aborted after radiation levels briefly surged. but the public no longer knows what to believe. 77-year-old emperor ahito made a rare tv address. "i am deally concerned about the nuclear situation because it is so unpredictable," he said. these enormous lines in sendai are people waiting for one bus out of town. back in the di